Aug. 15,1931 
Bacteriology and Chemistry of Different Silages 
787 
is due principally to the action of plant enzyms. Plant enzyms and 
microorganisms are both concerned in the formation of ammonia, the 
former being the more important. 
The formation of ammonia occurred in silage treated with 2 per cent 
chloroform, which inhibits the growth of bacteria, and in silage sterilized 
and inoculated; but more ammonia was formed in the chloroformed 
silage than in that sterilized and inoculated. It will be noted that the 
increase in acid-producing organisms and the formation of ammonia are 
very well correlated. It is probable that the acid-producing organisms 
did attack the proteins, decomposing them with the formation of the 
ammonia. It has been shown by Bertrand and Weissweiller (3), Heine- 
man and Hefferan (10), and Hastings, Evans, and Hart (8, 9) that the 
lactic bacilli do have a digestive action on protein. Hart, Flint, and 
Evans (7), working on the action of certain bacteria in regard to the 
ripening of cheddar cheese, found that Bacillus casei had the ability to 
produce ammonia. Hunter (12) in an article on alfalfa silage suggests 
that a small part of the protein hydrolysis may be caused by the ability 
of acid-producing organisms to utilize protein as a source of energy in 
the absence of carbohydrates. 
The largest number of yeasts were found in the first few days of the 
fermentation. They increased in number until all the free oxygen was 
consumed, then decreased. Lamb ( 14) states that alcohol is formed 
first by enzyms and later by yeasts. It is more easy to believe 
alcohol is formed first by yeasts and later by enzyms, because yeasts 
are present in greater numbers at the beginning of fermentation. 
The only difference noted in the fermentation of Canada field pea and 
oat silage from that of com silage was in the number of organisms belong¬ 
ing to the bulgaricus group. There were more organisms belonging to this 
group in corn silage than in silage composed of Canada field peas and oats. 
No difference could be noted in the fermentation of corn silage when 
compared with com and soybean silage. 
CONCLUSIONS 
(1) From the bacteriological and chemical analysis little difference 
can be noted between the fermentations taking place in silage composed 
of Canada field peas and oats, corn and soybeans, and corn only. There 
was a larger number of organisms belonging to the bulgarious group in 
corn silage than in the other types of silage studied. 
(2) Production of acids was due to microorganisms. 
(3) Yeasts apparently had little effect upon the fermentation of silage 
except during the first few days. 
(4) Plant enzyms were chiefly responsible for the hydrolysis of protein 
with formation of amino nitrogen. 
(5) The formation of ammonia was due to both enzyms and micro¬ 
organisms. 
